Washington (CNN)In his closed interview with the staff of the Senate intelligence committee, White House senior adviser and presidential son-in-law Jared Kushner did not share the existence of his personal email account, which he has used for official business, CNN has learned.

The emphasis in the letter on “all other” personal accounts not known by the committee would seem to be a reflection of the frustration the committee leaders feel with that fact that Kushner was not up-front about the existence of his personal email account and their desire for him to cover the bases of all his possible communications avenues when responding to their letter. This issue could become more serious if there emerge any emails or communications related to the investigation into Russian interference in the 2016 election that Kushner has not turned over, and whether he did so with the express purpose of concealing information from the committee.

Kushner’s attorney, Abbe Lowell, told CNN, “It is perfectly normal that the committees would want to make sure that they received all pertinent records. We did review this account at the time and there were no responsive or relevant documents there. The committee was so informed when documents were produced and there is no issue here.”

The Senate intelligence committee had no official comment.

The chairman of the committee, North Carolina Republican Richard Burr, and the vice chair, Virginia Democrat Mark Warner, learned of the existence of the personal email account, which Kushner used from January through August of this year, via the media. Their letter specifically references a CNN digital story headlined “Attorney: Kushner used private email account to talk to WH officials.”

CNN obtained the letter labeled “COMMITTEE SENSITIVE” via the self-styled “email prankster,” a man in the UK who has several times impersonated members of the orbit around President Donald Trump to others in that circle.

Earlier this week, the prankster pretended to be Kushner and wrote to Kushner’s real attorney, Lowell, about the (fictitious) adult content of emails he had shared with White House officials, as covered by Business Insider. Apparently, earlier Thursday, when Lowell attempted to forward the very real letter from the very legitimate Senate intelligence committee leaders, his email auto-fill supplied the address of the very fake Kushner account run by the prankster. A person familiar with the email transmission told CNN it was inadvertently forwarded to the prankster’s address.

In a statement to CNN, the prankster explained why he does this: “The original prank’s intention was to meet hypocrisy and cronyism with levity and a soupçon of embarrassment, instead of giving into the well worn grooves of anger and frustration. There’s a dash of modern-day surrealism creeping in at times, and this is evolving the more friends I make in the US.”

Kushner has been criticized in the past for initially not disclosing more than 100 contacts with foreign leaders including those from Russia, as well as ownership of a multimillion dollar tech company with links to Goldman Sachs and businessmen Peter Thiel and George Soros. Kushner was also one of three top campaign officials or surrogates who failed to disclose a June 2016 meeting with a woman billed as being with the Russian government and having incriminating information on Hillary Clinton.